bruce destroys paul! hes done everything that paul has and more, bruce has more range than alot of the metal singers, and if you want to hear bruce do gruff vocals, check out fear of the dark, or no prayer for the dying, they have some pretty burly bruce vocals in them. try to imagine paul doing rock in rio!? the energy that bruce displays just wouldnt be there.
also , blaze bailey has an incredibly dark voice, that no one will be able match. the x factor album has grown to be one of my favorites too.(next to somewhere in time).